Electronic guillotine vitrectomy cutter

ABSTRACT

A vitrectomy apparatus is provided, including a disposable cutter that incorporates a linear voice coil motor to generate consistent and rapid guillotine action without the use of a rotary motor or traditional linear motor. The apparatus includes voice coil actuator to provide for a forward and backward reciprocating motion cutting blade.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of and claims priority to U.S. patentapplication Ser. No. 15/725,182, filed Oct. 4, 2017, which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to the field of surgical handpieces, and, more specifically, to vitrectomy surgical hand pieces forocular surgical procedures.

BACKGROUND

Certain surgical procedures, such as phacoemulsification surgery, havebeen successfully employed in the treatment of certain ocular problems,such as cataracts. Phacoemulsification surgery utilizes a small cornealincision to insert the tip of at least one phacoemulsification handheldsurgical implement, or hand piece, through the comeal incision. The handpiece includes a needle which is ultrasonically driven once placedwithin the incision to emulsify the eye lens, or to break the cataractinto small pieces. The broken cataract pieces or emulsified eye lens maysubsequently be removed using the same hand piece, or another handpiece, in a controlled manner. The surgeon may then insert a lensimplant into the eye through the incision. The incision is allowed toheal, and the result for the patient is typically significantly improvedeyesight.

As may be appreciated, the flow of fluid to and from a patient through afluid infusion or extraction system, and thus the control of fluids andfluid pressure through the phacoemulsification hand piece, is criticalto the procedure performed. Different medically recognized techniqueshave been utilized to control the fluid flow during the lens removalportion of the surgery. Among these, one popular technique is asimultaneous combination of phacoemulsification, irrigation andaspiration using a single hand piece. This method includes making theincision, inserting the handheld surgical implement to emulsify thecataract or eye lens, and, simultaneously with this emulsification,having the hand piece provide a fluid for irrigation of the emulsifiedlens using a sleeve that surrounds a needle and a vacuum for aspirationof the emulsified lens and inserted fluids.

Currently available phacoemulsification systems, such as those mentionedabove, typically include a variable speed peristaltic pump and/or vacuumpump, a vacuum sensor, an adjustable source of ultrasonic power, and aprogrammable microprocessor with operator-selected presets forcontrolling aspiration rate, vacuum and ultrasonic power levels. Thephacoemulsification hand piece is interconnected with a control consoleby an electric cable for powering and controlling a piezoelectrictransducer that drives the action of the hand piece. Tubing providesirrigation fluid to the eye through the hand piece and enableswithdrawal of aspiration fluid from an eye through the hand piece.

Generally, irrigation and aspiration are employed by the surgeon usingthe device to remove unwanted tissue and maintain pressure within theeye. Moreover, the use of, and particularly the pressurization of, theirrigation fluid is critical and may, for example, prevent the collapseof the eye during the removal of the emulsified lens. Irrigation fluidpressure is also used to protect the eye from the heat generated by theultrasonic cutting needle and may suspend fragments created during thesurgery in fluid for more easy removal through aspiration.

Current phacoemulsification systems use either an electronic rotaryvitrectomy cutter or a pneumatic driven vitrectomy cutter. Existingelectronic rotary vitrectomy cutters use an oscillating cutting actionwhich can result in an incomplete cut. This incomplete cut can pullvitreous material rather than cutting it. While a pneumatic vitrectomyrequires a significant amount of hardware components, both in terms ofcost and space, along with complex algorithms to ensure the system isproviding sufficient pneumatic pressure to complete a cut.

Based on the foregoing, it would be advantageous to provide a systemthat enables the combination of an electronic rotary vitrectomy cutterdrive with the mechanical action of a pneumatic cutter.

BRIEF SUMMARY OF THE INVENTION

By combining the drive of a rotary vitrectomy cutter with the mechanicalaction of a pneumatic cutter, the development of a disposable cutterthat enables a build at lower cost, is smaller, and is simpler isrealized. The cutter incorporates a Linear Voice Coil Motor (LVCM) intothe design to generate consistent and rapid guillotine action in asmaller design without the use of a rotary motor or the size of a linearmotor.

The present invention comprises a vitrectomy apparatus, furthercomprising a vitrectomy hand piece comprising a guillotine cuttingdevice comprising a bobbin (which may be wound with magnet wire),creating a coil that when a current is run through it creates anelectromagnet, permanently fixed to an internal cutting shaft, a magnetpermanently (for example, a ring shaped magnet) affixed to the internalcenter of a shell composed of ferrous materials of the guillotinecutting device, and a controller configured to control operation of theinternal cutting shaft, wherein the controller is configured to controlmotion of the bobbin in response to an application of voltage causingthe internal cutting shaft to move forward and backwards with differencein polarity of the permanently fixed magnet. The vitrectomy apparatusmay also comprise a tube with at least one first opening at the distalend of the hand piece communicatively connected to at least one secondopening at the proximal end to allow for aspirated fluid to exit fromthe apparatus.

The present invention comprises a method of controlling a guillotinecutting device by providing a bobbin wound with one or more pieces ofmagnetic wiring and permanently affixed to an internal cutting shaft,the one or more pieces of magnetic wiring capable of generating amagnetic field, providing at least one magnet affixed to the internalcenter of a shell of the guillotine cutting device, and generating atleast one magnetic field from a provided voltage, wherein the bobbinmoves forward and backward based on a difference in polarity of themagnet in response to the magnetic field. The magnet core of the presentinvention may be permanently affixed to the internal cutting shaft. Thepresent invention may provide voltage that is pulsed and may be between1 and 24 volts and the voltage may control the speed of the bobbinmovement. The present invention may also include at least one heat sink.

BRIEF DESCRIPTION OF THE DRAWINGS

This disclosure is illustrated by way of example and not by way oflimitation in the accompanying figure(s). The figure(s) may, alone or incombination, illustrate one or more embodiments of the disclosure.Elements illustrated in the figure(s) are not necessarily drawn toscale. Reference labels may be repeated among the figures to indicatecorresponding or analogous elements.

The detailed description makes reference to the accompanying figures inwhich:

FIG. 1 illustrates a prospective view of an embodiment of the presentinvention;

FIG. 2A illustrates a top view of the surgical device;

FIG. 2B illustrates a side view of the surgical device;

FIG. 2C illustrates a rear view of the surgical device;

FIG. 2D illustrates a front view of the surgical device;

FIG. 2E illustrates a top view of the surgical device;

FIG. 2F illustrates a side view of the surgical device;

FIG. 2G illustrates a rear view of the surgical device;

FIG. 2H illustrates a front view of the surgical device;

FIG. 3A illustrates a cross-sectional view of the surgical device in anopened state;

FIG. 3B illustrates a cross-sectional view of the surgical device in aclosed state;

FIG. 3C illustrates a cross-sectional view of the surgical device in anopened state;

FIG. 3D illustrates a cross-sectional view of the surgical devicesimilar to FIG. 3B shown in a closed state and with an optional spring;

FIGS. 4A and 4B illustrate cross sectional views of embodiments of thepresent invention;

FIG. 5A illustrates a cross-sectional view of the surgical device in anopened state in at least one alternate embodiment; and

FIG. 5B illustrates a cross-sectional view of the surgical device in aclosed state in at least one alternate embodiment.

DETAILED DESCRIPTION

The figures and descriptions provided herein may have been simplified toillustrate aspects that are relevant for a clear understanding of theherein described apparatuses, systems, and methods, while eliminating,for the purpose of clarity, other aspects that may be found in typicalsimilar devices, systems, and methods. Those of ordinary skill may thusrecognize that other elements and/or operations may be desirable and/ornecessary to implement the devices, systems, and methods describedherein. But because such elements and operations are known in the art,and because they do not facilitate a better understanding of the presentdisclosure, for the sake of brevity a discussion of such elements andoperations may not be provided herein. However, the present disclosureis deemed to nevertheless include all such elements, variations, andmodifications to the described aspects that would be known to those ofordinary skill in the art.

Embodiments are provided throughout so that this disclosure issufficiently thorough and fully conveys the scope of the disclosedembodiments to those who are skilled in the art. Numerous specificdetails are set forth, such as examples of specific components, devices,and methods, to provide a thorough understanding of embodiments of thepresent disclosure. Nevertheless, it will be apparent to those skilledin the art that certain specific disclosed details need not be employed,and that exemplary embodiments may be embodied in different forms. Assuch, the exemplary embodiments should not be construed to limit thescope of the disclosure. As referenced above, in some exemplaryembodiments, well-known processes, well-known device structures, andwell-known technologies may not be described in detail.

The terminology used herein is for the purpose of describing particularexemplary embodiments only and is not intended to be limiting. Forexample, as used herein, the singular forms “a,” “an,” and “the” may beintended to include the plural forms as well, unless the context clearlyindicates otherwise. The terms “comprises,” “comprising,” “including,”and “having” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The steps, processes, and operations described herein are notto be construed as necessarily requiring their respective performance inthe particular order discussed or illustrated, unless specificallyidentified as a preferred or required order of performance. It is alsoto be understood that additional or alternative steps may be employed,in place of or in conjunction with the disclosed aspects.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present, unless clearlyindicated otherwise. In contrast, when an element is referred to asbeing “directly on,” “directly engaged to,” “directly connected to,” or“directly coupled to” another element or layer, there may be nointervening elements or layers present. Other words used to describe therelationship between elements should be interpreted in a like fashion(e.g., “between” versus “directly between,” “adjacent” versus “directlyadjacent,” etc.). Further, as used herein the term “and/or” includes anyand all combinations of one or more of the associated listed items.

Yet further, although the terms first, second, third, etc. may be usedherein to describe various elements, components, regions, layers and/orsections, these elements, components, regions, layers and/or sectionsshould not be limited by these terms. These terms may be only used todistinguish one element, component, region, layer or section fromanother element, component, region, layer or section. Terms such as“first,” “second,” and other numerical terms when used herein do notimply a sequence or order unless clearly indicated by the context. Thus,a first element, component, region, layer or section discussed belowcould be termed a second element, component, region, layer, or sectionwithout departing from the teachings of the exemplary embodiments.

The present design provides a system and method for a high-speedguillotine action vitrectomy cutter that may be used to precisely setand vary the cutting speed of the associated cutting blade mechanismover a wide range of operational speeds.

While the present design may be employed in various systems involvingcutting blades, it is illustrated herein in an exemplaryphacoemulsification-vitrectomy system. The present design is directed toaccurate, reliable, and efficient use of a voice coil actuator toprovide for a forward and backward reciprocating motion cutting blade ina vitrectomy handpiece used in a medical instrument system. The presentdesign will be discussed herein with a particular emphasis on a medicalor hospital environment, where a surgeon or health care practitionerperforms. For example, an embodiment of the present invention is aphacoemulsification surgical system that comprises an integratedhigh-speed control module for the vitrectomy handpiece. The surgeon orpractitioner may adjust or set the blade speed via a graphical userinterface (GUI) module, a switch located on the handpiece, or a footpedal switch to control the high-speed vitrectomy handpiece.

As illustrated in FIG. 1 , the present invention may provide anergonomic hand piece 100 which may be held easily by the fingers and/orhands of an operator and which may house a mechanism suitable to providea vitrectomy cutting mechanism. The body of the surgical instrument mayinclude texture on the exterior to aid with the actual gripping of thehand piece. As illustrated by the views 200A-200H presented in FIGS.2A-2H, the hand piece body may contain at least one feature indicativeof the location of the cutter opening of the surgical instrument toprovide a tactile indicator to the user of the device as to theorientation of the hand piece. Such a feature may include a detent, araised portion, or a combination thereof, for example. In at least onenon-limiting embodiment, as illustrated in FIGS. 2E-2H, aspiration line202 may be outside or externally located in relation to the body of thedevice to improve upon the strength of the device's drive mechanism.Aspiration line 202 may be fastened permanently or semi-permanentlyusing fastener 204.

In an embodiment of the present invention, the surgical instrument maycomprise a primary shaft extending out from the body of the hand piecewhich may further comprise at least one port and/or at least one cuttingelement. The primary shaft may also include at least one of an openingat the distal end for aspiration and at an opening at the proximal endfor aspirated fluid and material to exit the at least one shaft portionof the surgical instrument. The primary shaft may be sheathed in anouter shaft which may be communicatively attached to the hand piece andmay, for example, provide rigidity and/or guidance to the primary shaft.

The surgical instrument may contain a permanent magnet that is fixedsubstantially within the center of a shell. The shell, which maycomprise soft iron, may preferably be of a steel composition or otherferrous materials. The permanent magnet may be affixed to the shell andmay be in electromagnetic communication with at least one voice coil.Alternatively, the permanent magnet may be a ring-shaped magnet. Thevoice coil may be a single phase linear voice coil actuator, which mayprovide direct, cog-free linear motion that is substantially free ofbacklash, irregularity, and/or energy loss which may result fromconverting rotary to linear motion. The voice coil may also comprise atubular coil of wire situated within a radially oriented magnetic field.

In an embodiment of the present invention, the linear voice coil motormay be composed of two parts, a cylinder composed of ferrous materialswith a cylindrical magnet in the center (i.e., magnet core) and a wirewrapped bobbin which may be energized to create the opposing magneticfield which drives the motor. The linear voice coil may also be designedand oriented in two different directions. In at least one embodiment, abobbin forward design may fix the magnet core in place and move thebobbin. In another embodiment, a magnet forward design may fix thebobbin in place. In yet another embodiment of the present invention, apermanent magnet may be affixed to the center of a bobbin and surroundedby an iron magnet housing. Alternatively, the hand piece housing may becomposed entirely of magnetic materials rather than iron. The core ofthe magnet housing may therefore be an iron core or another permanentmagnet at the center.

A gap may exist between the shell and the permanent magnet, the shelland the voice coil, and the voice coil and the permanent magnet. The gapmay be filled with air, a gas, and/or fluid, such as aspirated fluidfrom the surgical site as will be discussed herein. The air and/or fluidin the gap provides freedom of movement of the voice coil and mayprovide cooling of the voice coil and surrounding components. In anembodiment of the present invention, the axial length of the coil mayexceed that of the magnet by the amount of coil travel which may providea superior force-to-power ratio and allow for greater heat dissipation.

As illustrated in FIGS. 3A and 3B, cross-sectional views illustrating anelectronic guillotine vitrectomy cutting system within a surgical handpiece illustrate the guillotine cutting mechanism in the “open” or“backward” position, and in the “closed” or “forward” position,respectively. As illustrated in FIGS. 3A and 3B, the at least onepermanent or solid magnet 308 may be affixed to a magnet housing, suchas shell 312, at the distal end and may have at its proximate end anassembly comprising a solid magnet cap 314 and a dampening material 316(for example for minimizing or eliminating vibration and/or sound). Thecap may be comprised of ferrous materials and have a high iron count.Even further, cap 314 may include a sharp corner on the end face nearestto the shell at the most distal end. Similarly, the distal end of theshell 312 closest to the cap 314 may also have a substantially sharpand/or squared corner which, when taken together with the shape of thecap, may enhance the magnetic field density which may act on the voicecoil. Dampening material 316 may be silicone, rubber, or other foam-typevibration dampening or dissipating material and/or may be a spring orspring-like device.

The voice coil 310 may be wrapped in motor winding wire of either around or flattened profile wrapped around a bobbin. The bobbin may becomposed of plastic, metal, rubber, or a combination thereof. The bobbinwindings may be electrically connected to a system and the bobbin may bepermanently fixed to the internal shaft 318. Internal shaft 318 mayextend axially through the body of the surgical instrument and coaxiallythrough external shaft 304. Voice coil 310 may similarly comprisesubstantially sharp and/or squared corners 320 which, when takentogether with the shape of the cap 314 and shell 312, may enhance themagnetic field density which may act on the voice coil.

In at least one embodiment of the surgical instrument, during operation,the distal end of the external shaft 304 may contact the interior of apatient's eye. Shaft 318 may be permanently affixed to coil 310. Theinternal shaft 304 may include opening 306 in the sidewall near thedistal end of internal shaft 318. The opening 306 may comprise a portallowing for an aspiration path into the patient's eye and may furthercomprise at least one surface suitable for providing a cutting action,such as a blade portion.

In an embodiment of the invention, a drive voltage (between 1-24 Volts,preferably 1-5 Volts) may cause the voice coil 310 to move in a back andforth motion in response to differences in polarity of the drivevoltage. The bobbin motion may or may not be constrained axially withinthe body of the surgical instrument. When the voltage differentialapplied to the bobbin windings is zero, no magnetic field is generatedby the bobbin windings. When the voltage differential is greater thanzero, a magnetic field is generated causing a magnetic polarity oppositeof the fixed magnet 308 which in turn causes the bobbin to move forwardand extend the internal shaft 318. When the voltage differential iszero, no magnetic field is generated; causing the bobbin to movebackward towards the fixed magnet 308 and the internal shaft 318 isretracted. As the voice coil 310 moves in the back and forth motion, itmay be bounded by either silicone, rubber, or other foam-type vibrationdampening or dissipating material. In an embodiment, the voice coil maybe bounded by a hard material, including, but not limited to, metal orplastic. A spring 316′, as schematically represented in FIG. 3D, mayalso be included to stabilize or slow the bobbin speed as the bobbinmoves from forward stroke to backward stroke. Such a stabilization orslowing process may reduce vibration of the surgical instrument.

As the internal shaft moves forward and backwards, it may pass through aseal at the front of the hand piece housing as well as a seal at therear of the hand piece housing. The use of a front seal may ensure thatnear maximum vacuum is applied through the aspiration hole provided inthe internal shaft and that the vacuum is not lost through the spacebetween the exterior surface of the internal shaft and the interior ofthe exterior shaft. The seal at the back of the device may create anopen space within the barbed fitting where a vacuum may be provided froman aspiration line from the surgical system (not shown). The rear sealmay create the aforementioned vacuum which may be applied through theopen end of the internal shaft which extends the vacuum to opening 306.The seals may be integrated with to the surgical instrument byover-molded rubber, silicone-type materials, or separate components,such as O-rings, canted coil spring seals, or separate moldedcomponents, for example.

The backward/forward motion of internal shaft 318 may be controlled by amagnetic field as previously described above. Dampening material 316 maybe utilized to control forward and rear positioning of voice coil 310 inrelation to permanent magnet 308. Consistent and rapid guillotine actionis realized by the linear voice coil motor to produce the necessary cutsper minute for anterior vitrectomy operation.

In an embodiment of the present invention, as illustrated in FIG. 3C,aspiration line 202, may be communicatively connected to internal shaft318. The aspiration line 202 may be positioned along the longitudinalaxis of internal shaft 318 and may be positioned proximate to theintersection of the internal shaft 318 and voice coil 310. Such anarrangement may allow the internal shaft 318 to terminate in the voicecoil 310 and not otherwise interfere with or penetrate the solid magnetassembly. In this embodiment of the present invention, the constructionand performance of the solid magnet assembly may be simplified andimproved by not necessitating, for example, the milling of a passagethrough the solid magnet. Aspiration line 202 may be affixedmechanically to internal shaft 318 and may comprise a flexibleattachment means suitable to withstand the movement of internal shaft318.

As illustrated in FIG. 4A, a cross section 400 taken towards theproximate end of the voice coil motor assembly illustrates guiding rails402 in contact with shell assembly 404 for use in providing motioncontrol over the voice coil 406. As illustrated, a set of threeindependent guide rails are shown. As would be understood by thoseskilled in the art, the number and size of rails may be varied dependingon design requirements. Although the rails may take on various shapes,guiding rails 402 comprise angled and/or chamfered corners to minimizeunwanted movement and/or vibrations. Similarly, as illustrated in crosssection 410 of FIG. 4B taken near the distal end of the voice coilassembly, and at least partially independent plurality of guiding rails408 may be provided to reduce movement and vibrations of the permanentaffixed magnet relative to the shell assembly 404.

As illustrated in FIGS. 5A and 5B, cross-sectional views 500A, 502A,500B and 502B illustrate an alternative electronic guillotine vitrectomycutting system in accordance with the disclosed invention. FIG. 5A showsthe cutter in a backward position and FIG. 5B shows the cutter in aforward position. In the alternate embodiment, magnet housing or shell504 and voice coil 506 may be permanently fixed to the internal shell.Magnet housing 504 may be comprised of ferrous materials. In thisembodiment, magnet 510 would move back and forth in response to voltageapplication in the manner described herein. Moving magnet 510 may beaffixed to cutting shaft 512 which is contained by the external shaftwith opening. Dampening material 508 may be provided in the front andrear to reduce noise and/or vibration. In this embodiment, the movingmass is reduced which results in reduced vibration an improved thermaldissipation of the heat created by the coil. The fixed coil 506 may beequipped with a passive heat exchanger such as a heat sink.

In the foregoing detailed description, it may be that various featuresare grouped together in individual embodiments for the purpose ofbrevity in the disclosure. This method of disclosure is not to beinterpreted as reflecting an intention that any subsequently claimedembodiments require more features than are expressly recited.

Further, the descriptions of the disclosure are provided to enable anyperson skilled in the art to make or use the disclosed embodiments.Various modifications to the disclosure will be readily apparent tothose skilled in the art, and the generic principles defined herein maybe applied to other variations without departing from the spirit orscope of the disclosure. Thus, the disclosure is not intended to belimited to the examples and designs described herein, but rather is tobe accorded the widest scope consistent with the principles and novelfeatures disclosed herein.

The invention claimed is:
 1. A method of controlling a guillotinecutting device, the device comprising: providing a bobbin wound with oneor more pieces of magnetic wiring and affixed to an internal cuttingshaft, the one or more pieces of magnetic wiring capable of generating amagnetic field; providing at least one magnet in communication with thebobbin; and generating at least one magnetic field from a providedvoltage, wherein the bobbin moves forward and backward based on adifference in polarity of the magnet in response to the magnetic field,wherein at least one of a shape of the bobbin and a shape of the atleast one magnet enhances the magnetic field density of the generatedmagnetic field.
 2. The method of claim 1, wherein the at least onemagnet is affixed to an internal center of a shell of the guillotinecutting device.
 3. The method of claim 1, wherein the provided voltageis pulsed.
 4. The method of claim 1, wherein the provided voltage isbetween 1 and 5 volts.
 5. The method of claim 1, wherein the providedvoltage controls the speed of the bobbin movement.
 6. The method ofclaim 1, further comprising providing at least one heat sink.
 7. Themethod of claim 1, wherein a bobbin motion is bounded by one or moredampening materials.
 8. A method of controlling a guillotine cuttingdevice, the device comprising: providing a bobbin wound with one or morepieces of magnetic wiring and affixed to an internal cutting shaft, theone or more pieces of magnetic wiring capable of generating a magneticfield; providing at least one magnet in communication with the bobbin;and generating at least one magnetic field from a provided voltage,wherein the bobbin moves forward and backward based on a difference inpolarity of the magnet in response to the magnetic field, wherein theprovided voltage is between 1 and 24 volts.
 9. A method of controlling aguillotine cutting device, the device comprising: providing a bobbinwound with one or more pieces of magnetic wiring and affixed to aninternal cutting shaft, the one or more pieces of magnetic wiringcapable of generating a magnetic field; providing at least one magnet incommunication with the bobbin; and generating at least one magneticfield from a provided voltage, wherein the bobbin moves forward andbackward based on a difference in polarity of the magnet in response tothe magnetic field, wherein bobbin movement is bounded by one or moredampening materials comprising a spring.
 10. A method of controlling aguillotine cutting device, the device comprising: providing a bobbinwound with one or more pieces of magnetic wiring and affixed to aninternal cutting shaft, the one or more pieces of magnetic wiringcapable of generating a magnetic field; providing at least one magnet incommunication with the bobbin; and generating at least one magneticfield from a provided voltage, wherein the bobbin moves forward andbackward based on a difference in polarity of the magnet in response tothe magnetic field, wherein bobbin movement is bounded by one or moredampening materials fixed to the magnet.
 11. The method of claim 10,wherein the one or more dampening materials comprise one or more ofsilicone, rubber, foam, metal, or plastic.